This will allow the key to have full access to update the zone 'example.com'. You might want to grant more restricted access in which case you should investigate update-policy. Here's an example to allow our key to update the A record for the same name(grant <key> <type> <zone> <record-types>):

DHCP client config

Many dhcp clients will have a mechanism to run arbitrary scripts when certain DHCP events occur, such as binding a new IP address. The event 'BOUND' is defined as "The DHCP client has done an initial binding to a new address".

nsupdate(1) is a tool that is distributed with BIND that can submit updates to BIND.

dhcpcd

In order to 'hook into DHCP events', dhcpcd can run scripts. Various OS distributions will include their own, although you can specify. On the system I'm looking, at the script /lib/dhcpcd/dhcpcd-run-hooks runs scripts in the directory /lib/dhcpcd/dhcpcd-hooks. All I need to do is put a script in that directory. The script itself is just a invocation of nsupdate, see below: